After you have determined that your troubleshooting attempts have not resolved the problem, contact Cisco TAC or your technical support representative.

Gathering Information

This section describes the tools that are commonly used to troubleshoot problems within your network. Specific troubleshooting articles may include additional tools and commands specific to the symptoms and possible problems covered in that article.

Note:

You should have an accurate topology of your network to isolate problem areas. Contact your network architect for this information.

Use the following commands to gather general information on your device:

show module

show version

show running-config

show logging log

show interfaces brief

show vlan

show spanning-tree

show {ip | ipv6} routing

show processes | include ER

show accounting log

Verifying Ports

Answer the following questions to verify that your ports are connected correctly and are operational:

Are you using the correct media (copper, optical, fiber type)?

Is the media broken or damaged?

Is the port LED green on the module?

Is the interface in the correct VDC?

Use the show vdc membership command to check which VDC that the interface is a member of. You must log into the device with the network-admin role to use this command.

Overview of Symptoms

This article uses a symptom-based troubleshooting approach that allows you to diagnose and resolve your Cisco NX-OS problems by comparing the symptoms that you observed in your network with the symptoms listed in each chapter.

By comparing the symptoms in this publication to the symptoms that you observe in your own network, you should be able to diagnose and correct software configuration issues and inoperable hardware components so that the problems are resolved with minimal disruption to the network. Those problems and corrective actions include the following:

Identify key Cisco NX-OS troubleshooting tools.

Obtain and analyze protocol traces using SPAN and RSPAN or Ethanalyzer on the CLI.

Identify or rule out physical port issues.

Identify or rule out switch module issues.

Diagnose and correct Layer 2 issues.

Diagnose and correct Layer 3 issues.

Recover from switch upgrade failures.

Obtain core dumps and other diagnostic data for use by Cisco TAC or your customer support representative.

System Messages

The system software sends syslog (system) messages to the console (and, optionally, to a logging server on another device). Not all messages indicate a problem with your device. Some messages are purely informational, while others might help diagnose problems with links, internal hardware, or the device software.

System Message Text

Message text is a text string that describes the condition. This portion of the message might contain detailed information about the event, including terminal port numbers, network addresses, or addresses that correspond to locations in the system memory address space. Because the information in these variable fields changes from message to message, it is represented here by short strings enclosed in square brackets ([ ]). A decimal number, for example, is represented as [dec ].

PORT-3-IF_UNSUPPORTED_TRANSCEIVER: Transceiver for interface [chars] is not supported.

Each system message is followed by an explanation and recommended action. The action may be as simple as "No action is required." It may involve a fix or a recommendation to contact technical support as shown in the following example:

Error Message PORT-3-IF_UNSUPPORTED_TRANSCEIVER: Transceiver for interface [chars] is not supported.

Explanation Transceiver (SFP) is not from an authorized vendor.

Recommended Action Enter the show interface transceiver CLI command or similar DCNM command to determine the transceiver being used. Please contact your customer support representative for a list of authorized transceiver vendors.

syslog Server Implementation

The syslog facility allows the Cisco NX-OS device to send a copy of the message log to a host for more permanent storage. This feature allows you to examine the logs over a long period of time or if the Cisco NX-OS device is not accessible.

This example shows how to configure a Cisco NX-OS device to use the syslog facility on a Solaris platform. Although a Solaris host is being used, the syslog configuration on all UNIX and Linux systems is very similar.

syslog uses the facility to determine how to handle a message on the syslog server (the Solaris system in this example) and the message severity. Different message severities are handled differently by the syslog server. They could be logged to different files or e-mailed to a particular user. Specifying a severity level on the syslog server determines that all messages of that level and greater severity (lower number) will be acted upon as you configure the syslog server.

Note:

You should configure the syslog server so that the Cisco NX-OS messages are logged to a different file from the standard syslog file so that they cannot be confused with other non-Cisco syslog messages. Do not locate the logfile on the / file system. You do not want log messages to fill up the / file system. This example uses the following values:

syslog client: switch1

syslog server: 172.22.36.211

(Solaris) syslog facility: local1

syslog severity: notifications (level 5, the default)

File to log Cisco NX-OS messages to: /var/adm/nxos_logs

To configure the syslog feature on Cisco NX-OS, follow these steps:

switch1# config terminal

switch1(config)# logging server 192.0.2.1 6 facility local1

Use the show logging server command to verify the syslog configuration.

1. Modify /etc/syslog.conf to handle local1 messages. For Solaris, you must allow at least one tab between the facility.severity and the action (/var/adm/nxos_logs).

local1.notice /var/adm/nxos_logs

2. Create the log file.

touch /var/adm/nxos_logs

3. Restart the syslog process.

/etc/init.d/syslog stop

/etc/init.d/syslog start

syslog service starting.

4. Verify that the syslog process has started.

ps -ef |grep syslogd

root 23508 1 0 11:01:41 ? 0:00 /usr/sbin/syslogd

Test the syslog server by creating an event in Cisco NX-OS. In this case, port e1/2 was shut down and reenabled and the following was listed on the syslog server. The IP address of the switch is listed in brackets.

Troubleshooting with Logs

Cisco NX-OS generates many types of system messages on the device and sends them to a syslog server. You can view these messages to determine what events may have led up to the current problem condition that you are facing.

Viewing NVRAM logs

System messages that are priority 0, 1, or 2 are logged into NVRAM on the supervisor module. After a switch reboots, you can display these syslog messages in NVRAM by using the show logging nvram command.

Contacting Customer Support

If you are unable to solve a problem after using the troubleshooting suggestions in these articles, contact a customer service representative for assistance and further instructions. Before you call, have the following information ready to help your service provider assist you as quickly as possible:

Date that you received the switch

Chassis serial number (located on a label on the right side of the rear panel of the chassis)

Type of software and release number

Maintenance agreement or warranty information

Brief description of the problem

Brief explanation of the steps that you have already taken to isolate and resolve the problem